1. Field of the Invention
This invention relates to an apparatus for automatically controlling the position of a plurality of slitters for slitting a moving web.
More particularly, this invention relates to an apparatus for automatically controlling the position of a plurality of slitters for slitting a moving web of paper into a plurality of individual reels.
2. Information Disclosure Statement
In the papermaking art, individual customer orders specify particular reel width requirements. Consequently, a roll of paper on a winder which may be 260 or more inches (660.40 CMS) in width must be slit into a plurality of individual reels having the width specified in the order.
Traditionally, such slitting of a paper roll has necessitated the manual sliding of a plurality of slitter blades and slitter bands transversely relative to a paper web and the careful adjustment of each blade and corresponding slitter band to obtain the required reel widths.
Such manual adjustment of the slitter blades and slitter bands has not only proved to be a time-consuming operation but additionally, due to wear of the respective slitter blades, difficulties have been experienced with the production of reels that meet customer tolerances.
In the prior art, proposals have been set forth in which such slitter blades and slitter bands may be moved transversely relative to the moving web by means of electronic control mechanisms. However, such prior art proposals have not combined features enabling a completely computerized control system incorporating means for compensating for slitter blade wear.
U.S. Pat. No. 3,176,566 to Patterson teaches a remotely positioned slitter system for controlling the transverse disposition of a slitter blade and cooperating slitter band. However, Patterson does not teach a computer controlled positioning system or the use of a display monitor for displaying the relative dispositions of the blades and bands.
U.S. Pat. No. 3,488,479 to Keyes et al describes a slitter positioning system including a digital computer for controlling a plurality of slitter motors. However, the Keyes disclosure does not teach a control module associated with each respective blade and band.
U.S. Pat. No. 4,077,291 to Obenshain discloses a web slitting apparatus but it does not disclose a wear detection switch in combination with a computer control.
U.S. Pat. No. 4,252,044 to Yamashita et al discloses an automatic cutter positioning device for a gang slitter.
U.S. Pat. No. 3,540,340 to Koskela discloses a longitudinal sheet cutter.
U.S. Pat. No. 3,427,518 to Cloup discloses a digitally controlled positioning device.
U.S. Pat. No. 3,886,833 to Gunn et al teaches an apparatus for remotely positioning a web slitter.
U.S. Pat. No. 3,651,723 to Gallagher Jr. et al relates to a corrugated paperboard slitter scorer.
U.S. Pat. No. 3,691,698 to Shaller teaches an abrasive element dimension sensing mechanism.
U.S. Pat. No. 4,224,847 to Tokuno teaches a tool positioning apparatus which is adapted to position by numerical control a plurality of pairs of tools attached to a pair of parallel shafts.
Canadian Pat. No. 1,043,004 assigned to Jagenberg-Werk AG discloses a device which adjusts the spacing between a plurality of elements for cutting strip material lengthwise.
None of the aforementioned prior art proposals teach, in combination, an apparatus for automatically controlling the position of a plurality of slitters such that the slitters may be sent to designated locations and automatically adjusted to compensate for blade wear.
Therefore, it is a primary object of the present invention to provide an apparatus for automatically controlling the position of a plurality of slitters that overcomes the aforementioned inadequacies of the prior art proposals and provides a control system including a significant contribution to the art of web slitting.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters including an electronic control connected to a first and second driving means for selectively positioning the slitter blade and band adjacent to each other such that the web moving between the slitter blade and band is sheared by the interaction of the slitter with the band.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which the control means includes a first control module secured to the first driving means and a second control module secured to the second driving means.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters for slitting a moving web in which the control means includes a digital control computer connected to the modules for selectively controlling the modules and for sending the modules to a designated location along the rails.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters including a monitor connected to the control computer for displaying the positions of the respective slitter blade and band.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which a communication bus means connects the control computer and the modules for sequentially conducting control signals from the computer to the modules and for sequentially conducting command signals from the modules to the computer for positioning the slitter blade and band adjacent to each other.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which a wear detection switch means is disposed adjacent to the slitter blade for detecting slitter blade wear. The detection switch is connected to the first control module such that when the slitter blade wears a wear detection signal is generated and conducted from the first module to the computer for compensating for such slitter blade wear.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which the driving means are stepping motors.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which the control means includes a first and second comparator for detecting and counting signals from magnetic calibration disposed along the first and second rails respectively such that the first and second modules are sent to the designated locations along the rails using a predetermined number of stepping motor increments.
Another object of the present invention is the provision of an apparatus for automatically controlling the position of a plurality of slitters in which the wear detection switch means includes a proximity switch controlled by eddy currents generated in the vicinity of the slitter blade for positioning the slitter blade relative to the band.
Other objects of the present invention will be apparent to those skilled in the art from the detailed description and drawings of the present application.